I'm trying to figure out a way if it is possible to have 2 different sensors displayed with one of them showing instant results and the second an average of results.

I have been using a "for loo"p for the averaging with an SHT75 sensor, putting the readings into an array etc. The problem is, is that the time taken to read the sensor 10 times is many many seconds which means that my other sensor which is a pressure sensor is not being polled..

Is there anyway to continuously display the pressure sensor reading and average the SHT75 in the background?

Poll your real time sensor and display both its result and the average result continuously, but use timer interrupt to trigger the other sensor and code that calculates the average only when needed (in intervals).

Why wait 10 times? You could read each sensor continuously. Display the current read only during the first 9 reads. After the 10th read, then start displaying the average along with the current. At the next read, throw out the first read thus leaving the last 10 values read. On each 'read', continue throwing out the earliest value read and adding the latest value read to the 10 'reads'. - Scotty

Thanks everybody. Will try a few of the suggestions and see which works out best for this sensor. As teh temperatures could fluctuate wildly (intentionally). I reckon the a=b etc option is best as it will clear the buffers out reasonably quickly when I take the probe from room temperature into a hot air duct. But the other principle may well be useful for another project I'm doing.